I know others have posted that visual voice-mail is not working. The response has been that 3rs party apps sometimes don't work and contact the app developer. Visual Voicemail is not a 3rd party app - it is a Samsung app.
Hopefully it will be addressed in the next beta.
Thank you for your post. If you see any other technical issues, please send us an error report for them, as well. We apologize for the inconvenience and appreciate your contribution to the beta program.
One UI Beta Team.